New low-voltage, low-power dual supply bus switches

4th August 2007

Toshiba

ES Admin

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Toshiba Electronics Europe (TEE) has expanded its family of low power bus switches with two ultra-miniature, dual supply devices that are ideal for applications such as I2C level shifting. The TC7WPB306 and TC7WPB307 are high-speed CMOS 2-bit dual supply bus switches that can provide an interface between two nodes at differing voltage levels. Ultra-small packaging and low power operation make them particularly suitable for portable and other battery-powered equipment.

The basic bus switch functionality is the connection or isolation of two bus systems via an enable signal. On top of this each of the new devices can be connected to two independent power supplies to support bidirectional level shifting between a lower voltage (VCCA) and a higher voltage (VCCB) system. Level shifting functionality is enabled by simply adding pull-up resistors between the VCCA, VCCB supply and the A, B data line, respectively. The dual supply bus switch comes in variants of an active high output enable for the TC7WPB306 and an active low output enable for the TC7WPB307.
High-speed operation of the switches is enabled by a maximum propagation delay of 0.12ns.

Additionally, the new level shifting ICs support power-down protection at the output enable input and provide protection against static discharge and transient excess voltages. Machine model and human body model ESD performance is rated at greater than ±200V and ±2000V respectively.
Designed to minimise board space, the new devices are available in either CSON8 (CST8) or SSOP8 (US8) packaging.